* Speciasi berdivergen is the process of a species into two or more species.
* Speciasi has been observed many times in the controlled laboratory conditions and in the wild.
* In organisms that reproduce sexually, resulting speciation by reproductive isolation followed by genealogical divergence.
There are four mechanisms of speciation. The most commonly occurs in animals is
1. Speciasi Allopatrik
2. Speciasi Peripatrik
3. Speciasi Parapatrik
4. Speciasi Sympatrik
1. Speciasi Allopatrik:
* Speciasi that occurs in populations initially isolated geographically,
* This geographical barrier allows the population affected by environmental factors, just as food etc.
* The habitat fragmentation or migration.
* Selection under such conditions can produce rapid changes in appearance and behavior of organisms.
* Because the selection and hanyutan work freely in an isolated population
* The firm looks when it runs in a long time there will be a greater variation mutations, lead to intrinsic isolation that would lead to reproductive isolation that would preclude mixing of genes,
* The separation will eventually produce organisms that can mate will not intervene is formed speciasi
* Example Xylocopa nobilis (beetle wood) in Manado
2. Speciasi Peripatrik
* Speciasi which occurs when the used small populations of organisms become isolated in a new environment.
* This is different from the speciation alopatrik in terms of population size is smaller than the population of elders.
* In this case, is the loss of genetic variation that occurs when a new population founded by a number of individuals is very small.
* As a result of loss of genetic variation, the new population may change, either genotypes or phenotypes of the native population.
* In extreme cases this led to speciasi which later led to the formation evolution
* The loss of this genetic variation, leading to rapid speciation
* Because through genetics hanyutan quick and small selection of genes. Immediately occur speciasi
3. Speciasi Parapatrik
* Speciasi peripatrik speciation is similar in size small populations into new habitats,
* But unlike in the absence of physical separation between the two populations.
* Speciation This resulted from the evolution of mechanisms that reduce genetic flow between the two populations.
* In general, this occurs when there are drastic changes in habitat environments parental species.
* One example is the grass Anthoxanthum odoratum, which can undergo speciation parapatrik in response to localized metal pollution from mining.
* In this case, the plants evolved to be resistant to high levels of metals in the soil.
* Selection out against mixed marriages with parental population produces a change in flowering time, causing reproductive isolation.
* Selection out of a hybrid between the two populations can lead to "strengthening", which is an evolutionary trait that promote mating within the species,
* And the transitional character that occurs when two species become more distinct in appearance.
4. Speciasi Simpatrik
* The mechanism of speciation is the species that inhabit the same place bebrbeda berdivergen without geographic isolation or change in habitat.
* This mechanism is quite rare because only with a little gene flow would be to eliminate genetic differences between one part of the population with other populations.
* In general, simpatrik speciation in animals requires the evolution of genetic differences and the occurrence of random mating
* Examples of duck with a Mentor who is in the same habitat
* The impact of this mechanism will bring reproductive isolation
* One type of speciation simpatrik involve crossbreeding two related species, resulting in a hybrid species.
* This is not a common occurrence in animals because the animals are usually sterile hybrid. In contrast, hybridization generally occurs in plants, because plants often double the number of chromosomes, forming poliploid
* This makes the chromosomes from each parental species to form the corresponding pair during meiosis.
* One example Speciaisi with simpatrik mechanism is kketika plant Arabidopsis thaliana and Arabidopsis arenosa
* Of the Marriage produce new species Arabidopsis suecica.
* This happened about 20,000 years ago, and the speciation process has been repeated in the laboratory, allowing study of genetic mechanisms involved in this process. \
* Actually, doubling chromosomes in the species is a major cause of reproductive isolation, because half of the chromosome that will double the marriage is not commensurate with the organisms that chromosomes do not double.
Geographical isolation Finch birds in the Galapagos Islands produced more than a dozen new species merupalan indication that this variation leads to happen here speciasi
* Speciasi has been observed many times in the controlled laboratory conditions and in the wild.
* In organisms that reproduce sexually, resulting speciation by reproductive isolation followed by genealogical divergence.
There are four mechanisms of speciation. The most commonly occurs in animals is
1. Speciasi Allopatrik
2. Speciasi Peripatrik
3. Speciasi Parapatrik
4. Speciasi Sympatrik
1. Speciasi Allopatrik:
* Speciasi that occurs in populations initially isolated geographically,
* This geographical barrier allows the population affected by environmental factors, just as food etc.
* The habitat fragmentation or migration.
* Selection under such conditions can produce rapid changes in appearance and behavior of organisms.
* Because the selection and hanyutan work freely in an isolated population
* The firm looks when it runs in a long time there will be a greater variation mutations, lead to intrinsic isolation that would lead to reproductive isolation that would preclude mixing of genes,
* The separation will eventually produce organisms that can mate will not intervene is formed speciasi
* Example Xylocopa nobilis (beetle wood) in Manado
2. Speciasi Peripatrik
* Speciasi which occurs when the used small populations of organisms become isolated in a new environment.
* This is different from the speciation alopatrik in terms of population size is smaller than the population of elders.
* In this case, is the loss of genetic variation that occurs when a new population founded by a number of individuals is very small.
* As a result of loss of genetic variation, the new population may change, either genotypes or phenotypes of the native population.
* In extreme cases this led to speciasi which later led to the formation evolution
* The loss of this genetic variation, leading to rapid speciation
* Because through genetics hanyutan quick and small selection of genes. Immediately occur speciasi
3. Speciasi Parapatrik
* Speciasi peripatrik speciation is similar in size small populations into new habitats,
* But unlike in the absence of physical separation between the two populations.
* Speciation This resulted from the evolution of mechanisms that reduce genetic flow between the two populations.
* In general, this occurs when there are drastic changes in habitat environments parental species.
* One example is the grass Anthoxanthum odoratum, which can undergo speciation parapatrik in response to localized metal pollution from mining.
* In this case, the plants evolved to be resistant to high levels of metals in the soil.
* Selection out against mixed marriages with parental population produces a change in flowering time, causing reproductive isolation.
* Selection out of a hybrid between the two populations can lead to "strengthening", which is an evolutionary trait that promote mating within the species,
* And the transitional character that occurs when two species become more distinct in appearance.
4. Speciasi Simpatrik
* The mechanism of speciation is the species that inhabit the same place bebrbeda berdivergen without geographic isolation or change in habitat.
* This mechanism is quite rare because only with a little gene flow would be to eliminate genetic differences between one part of the population with other populations.
* In general, simpatrik speciation in animals requires the evolution of genetic differences and the occurrence of random mating
* Examples of duck with a Mentor who is in the same habitat
* The impact of this mechanism will bring reproductive isolation
* One type of speciation simpatrik involve crossbreeding two related species, resulting in a hybrid species.
* This is not a common occurrence in animals because the animals are usually sterile hybrid. In contrast, hybridization generally occurs in plants, because plants often double the number of chromosomes, forming poliploid
* This makes the chromosomes from each parental species to form the corresponding pair during meiosis.
* One example Speciaisi with simpatrik mechanism is kketika plant Arabidopsis thaliana and Arabidopsis arenosa
* Of the Marriage produce new species Arabidopsis suecica.
* This happened about 20,000 years ago, and the speciation process has been repeated in the laboratory, allowing study of genetic mechanisms involved in this process. \
* Actually, doubling chromosomes in the species is a major cause of reproductive isolation, because half of the chromosome that will double the marriage is not commensurate with the organisms that chromosomes do not double.
Geographical isolation Finch birds in the Galapagos Islands produced more than a dozen new species merupalan indication that this variation leads to happen here speciasi
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